Part of the Escambia County Jail that was damaged in the blast. Credit: NBC News

The explosion at a Florida jail may have been caused by the recent extreme weather in the region, a spokesperson has said.

"We have reports people heard an explosion and smelled gas. There was no fire," County spokeswoman Kathleen Castro said, adding that the blast may have been related to severe storms that have hit the southern United States.

"The facility did receive extensive flooding as a result of the rains yesterday," she said.

The wife of the man who was shot dead in a cinema row was struck by the same bullet that killed her husband when she put her hand in front of him as the gun was fired, Pasco County Sheriff’s Office said, according to The Tampa Tribune.

Nicole Oulson, 33, was treated for a gunshot wound to her hand and later released from hospital.

The couple were watching Lone Survivor at a cinema in Tampa, Florida, when a row over texting broke out with the alleged gunman, retired Tampa police officer Curtis Reeves Jr, and his wife.